In systems of Long Term Evolution Release.8 (LTE REL.8) to LTE REL.11, a state of a channel from a base station to a user equipment (UE) determines throughput from the base station to the UE. In a good channel state, the base station can transmit data to the UE using a high modulation and coding scheme (MCS) level, and the throughput of the system is also large; in a poor channel state, to control a bit error rate during data transmission, the base station can transmit data to the UE using a low MCS level. The base station determines, according to a channel state fed back by the UE, a coding rate and an MCS level used for transmitting data on this channel. To achieve a purpose of transmitting data to the UE at this coding rate, the base station needs to determine a transport block size that the delivered service data needs to occupy. When determining the transport block size, the base station generally determines, in a transport block size table (TBS table), according to the determined MCS level and frequency resources scheduled by the system, a transport block size used to carry the service data that the base station delivers to the UE.
In the prior art, in LTE REL.12, the base station transmits data to the UE using a transport block size determined according to an existing TBS table. However, a system overhead of an LTE REL.12 system is lower than system overheads of systems of LTE REL.8 to LTE REL.11, which causes a lower actual effective coding rate during the transmission and further affects throughput of the LTE REL.12 system.